The posts we make in reply to those who may or may not be trolls are the key, in my opinion.
I've already forgotten where I mentioned it, but that is exactly the point. Whether someone is a 'troll' or not, if a question is explicitly answered and dealt with in a reply or two, then the thread is essentially over. It's dead, pending further details or on topic questions. The fact of whether it was a troll is irrelevant, the claim was dealt with. Said troll could post ten more claims, as long as they were all dealt with and people didn't chime in and bump it every five minutes, then said troll is effectively helping us (until of course it crosses lines of spamming, offending, yada yada).
What we've seen instead, and often, is threads turning into opinions, into slagging each other, into accusations of this and that. As I said in a PM, there is always the option to simply not reply. A thread doesn't need twenty ever so slightly different ways of telling someone "No".
I'm aware we've called for, and acknowledge the reason of, flat out blocks and be done with it, but I'm questioning some of the calls made recently. Yeah, maybe they were trolls. But maybe they used the wrong choice of words or have a different sense of humour. In murky grey areas, swinging the banhammer willy nilly can always result in hitting the wrong head.